Gene Penaflor spent nearly three weeks in the California wilderness, sleeping under a fallen tree and eating whatever small game he could get his hands on, before he was rescued Saturday. The 72-year-old San Francisco man was recovered from the Mendocino National Forest, a 913,000-acre reserve some 200 miles north of San Francisco, after hunters heard Penaflor’s cries coming from a valley below.

NBC reported that Penaflor was taken to a hospital in nearby Ukiah and released to his family shortly afterwards. He returned to his home in Bernal Heights in San Francisco on Sunday, where he watched the 49ers game. His disappearance had weighed heavily on his family for weeks.

“My dad was found alive and well!” Gene Penaflor’s son Jeremy Penaflor wrote on his Instagram page under a photo of his father. “After two and a half weeks out there alone, he made it through! Thank you for all your thoughts and prayers!! This is the BEST BIRTHDAY GIFT EVERRRRRR!!!”

"If he decides to hunt in a couple of years, that's fine,” Jeremy Penaflor later told CNN. “But we joked around and said let's make it a camping trip."

According to CNN, Penaflor set out on a hunting expedition with a friend in late September, but became separated from his companion after he slipped down a steep slope and struck his head. The blow knocked Penaflor unconscious, and when he awoke, he became disoriented because a thick fog had rolled in. Instead of wandering around, Penaflor decided to stay put.

Although Penaflor had a hunting rifle with him, he was too tired and weak to use it, The Huffington Post reported. He instead resorted to eating algae from a nearby stream and trapping small game like lizards, frogs, snakes and squirrels.

"He knew that terrain like the back of his hand," Jeremy Penaflor told NBC News. "He's been hunting for 25 to 30 years. He reads survival magazines. I wouldn't say I lost hope. It was dwindling, he's 72 years old, but I knew knowing what he knew not to give up."

Temperatures in the area where Penaflor went missing dipped to 25 degrees Fahrenheit at night. The 72-year-old reportedly built a fire and insulated his body with dry leaves and grass to stay warm.

Penaflor went missing Sept. 24 after he and his hunting companion went separate ways to track a deer. When Penaflor didn’t rendezvous for lunch later that day, his partner reported him missing.

A search party went out into the wilderness with people from two dozen county and state law enforcement offices. Rescue dogs and helicopters were also deployed, but after four days, came up empty handed. Then a storm rolled in, cutting the rescue mission short.

But on Saturday, a hunting group chanced upon Penaflor after they heard him crying for help. They called 911, and were able to get Penaflor out of the woods using their coats and poles they made from tree branches to create a makeshift stretcher.

Penaflor was treated at the Ukiah Valley Medical Center, and released to his family on Sunday.